How To Configure CVM

Veritas Cluster File System (CFS)

CFS allows the same file system to be simultaneously mounted on multiple nodes in the cluster.

The CFS is designed with master/slave architecture. Though any node can initiate an operation to create, delete, or resize data, the master node carries out the actual operation. CFS caches the metadata in memory, typically in the memory buffer cache or the vnode cache. A distributed locking mechanism, called GLM, is used for metadata and cache coherency among the multiple nodes.

The examples here are :

1. Based on VCS 5.x but should also work on 4.x
2. A new 4 node cluster with no resources defined.
3. Diskgroups and volumes will be created and shared across all nodes.

Before you configure CFS

1. Make sure you have an established Cluster and running properly.
2. Make sure these packages are installed on all nodes:
VRTScavf Veritas cfs and cvm agents by Symantec
VRTSglm Veritas LOCK MGR by Symantec
3. Make sure you have a license installed for Veritas CFS on all nodes.
4. Make sure vxfencing driver is active on all nodes (even if it is in disabled mode).

During configuration, veritas will pick up all information that is set on your cluster configuration. And will activate CVM on all the nodes.
# cfscluster config

The cluster configuration information as read from cluster
configuration file is as follows.
Cluster : MyCluster
Nodes : serverA serverB serverC serverD
You will now be prompted to enter the information pertaining
to the cluster and the individual nodes.

Specify whether you would like to use GAB messaging or TCP/UDP
messaging. If you choose gab messaging then you will not have
to configure IP addresses. Otherwise you will have to provide
IP addresses for all the nodes in the cluster.

——- Following is the summary of the information: ——
Cluster : MyCluster
Nodes : serverA serverB serverC serverD
Transport : gab
———————————————————–
Waiting for the new configuration to be added.

========================================================

Cluster File System Configuration is in progress…
cfscluster: CFS Cluster Configured Successfully
Check the status of the cluster

Now let’s check the status of the cluster. And notice that there is now a new service group cvm. CVM is required to be online before we can bring up any clustered filesystem on the nodes.
# cfscluster status

serverA # mkfs -F vxfs /dev/vx/rdsk/mysharedg/mysharevol1
serverA # mkfs -F vxfs /dev/vx/rdsk/mysharedg/mysharevol2
Then add these volumes/filesystems to the cluster configuration so they can be mounted on any or all nodes. Mountpoints will be automatically created.
serverA # cfsmntadm add mysharedg mysharevol1 /mountpoint1
Mount Point is being added…
/mountpoint1 added to the cluster-configuration

# haconf -dump -makero
How to create a file system using VERITAS Volume Manager, controlled under VERITAS Cluster Server

Details:

Following is the algorithm to create a volume, file system and put them under VERITAS Cluster Server (VCS).
1. Create a disk group
2. Create a mount point and file system
3. Deport a disk group
4. Create a service group
Add following resources and modify attributes: